What Causes Prolonged Cracks, Bleeding And Swelling In Lower Lip?

I have cracked bleeding swollen bottom lip. It is as if the top layer of skin keeps coming off leaving a red raw layer that is burning and painful. Putting Vaseline on it makes it feel better but doesn t make the problem go away. I used to get a sun herpe every time I spent time in Southern Ca that would just go away on its own and stay in one location. This episode started a couple of years ago after spending a few days in N MN on a lake. I was in the sun all day and had been using a tinted burts bees lip balm. I finally went to the doctor-they checked for allergies and said that I was allergic to grass and trees and that it was probably due to the elements the products I was using and the allergy to grass. I used an oral steroid I think prednisone and the symptoms went away for awhile Since then I have had intermittent episodes that with th diminished by using over the counter products for dry lips. This time my lip is red, raw and now has an overlay of pussy white layer. I went to the doctor and they put me on antiviral and antibiotics yesterday and did a culture for impetigo and herpes. They said if one comes back positive then we will continue the treatment that applies. It has been ongoing for the last 6 months pretty consistently. It seems to be under control and then flairs up again.